Expansible mandrel



Oct. 3l, 1950 H. R. BILLETER EXPANSIBLE MANDREL Filed Feb. 4, 1949 hij mw. NQ,

eww www @N1 NN MQNN NN Patented Oct. 31, 1950 EXPANSIBLE: MANDREL Henry Robert Billeter, Highland Park, Ill., as,-

signor to Ammco Tools, Inc., North Chicago, Ill., a corporation of Illinois Application'February 4, 1949, Serial N0. 74,683

Claims.

l My invention relates to mandrels and it has to do particularly with an expansible and contractible mandrel suitable for use as a work piece assures accuracy in the maintenance of relationship of parts and' adjustment thereof.A

Another object is to provide an expansible mandrel in which the expanding pressure is applied uniformly to the expans'ible elements so that the elements are maintained in alignment and are expanded without `binding and with a minimum of effort.

Still another object is to provide a tool of the foregoing character in which all clearance or looseness between relatively movable parts of the tool is eliminated throughout its entire range of expansion.

A further object is to provide a tool of the foregoing character wherein the lrange of expansion of any tool of particular size is materially increased with all of the advantages hereinabove just stated.

An additional object is to provide an improved tool expanding means which insures the accomplishment of all of the foregoing advantages.

A more specific object is to provide a tool of the foregoing character in which acne-piece expanding element is used having channel and cam portions respectively receiving and underlying complementary-shaped cam portions spaced on an expansible element of the tool and extending radially inwardly of the tool to the bottom of the guide slot for the expansibl'e element when the expansible element is in its fully contracted position to provide increased expanding surfaces lconnected with the expanding element.

Other objects and advantages will become apparent from the following description taken in conjunction with the appended drawing where- Figure 1 is a side elevational view showing one form of expansible mandrel embodying the invention and supported on an angle plate such as may be used for a connecting rod aligner or the like;

Fig. 2 is an enlarged longitudinal verticalsectional view of the lmandrel shown in Fig. 1;

Fig. 3 is a transverse sectional view taken along the l-ine 3-3 vof Fig. 2;

Fig. 4 is a transverse-sectional view taken along the line 4--4 of Fig. 2;

Fig. 5 is a transverse sectional view taken along the line 5--5 of Fig. 2; and

Fig'. 6 is areduced top plan view -o-f an expander element for-the mandrel shown in Fig. 2.

Referring to the drawing, the mandrel illustrated comprises a body member I0 having -a reduced end portion II adapted to be received and supported in any suitable fixture with which the tool is to be used, for example, the upright plate I2 constituting part of a connecting rod aligner such as shown in Letters Patent YNo. 2,013,374 of Herman W. Zimmerman, granted September 3, 1935. The reduced end portion II snugly passes through an opening I3 in the plate I2 where it is secured by a washer I4 and a nut I5 threaded on the end portion I I. The reduced end portion II provides a shoulder I6 on the body member IIJ, the surface of which is disposed at with respect `to the axis of the body member and insures that the axis of the mandrel ywill be disposed at right angles to the face I 2a of the supporting plate I2. The other or outer end of the body member I0 has successively reduced diameters providing three step-like portions I'I, I8 and I9, respectively, forming shoulders or abutment surfaces 20, 2I and 22 which will be referred to hereinafter.

The body `member II) is cut away longitudinally thereof from end to end to form three circumferentially disposed guide slots 23 having their opposite side walls 24 and 25 (Fig. 3) disposed on opposite sides of and similarly spaced from an axial plane passed through the body member and are arranged parallel therewith. A bottom surface 2B of each guide slot 23 connects the opposite side walls 24 and 25 of the guide slot and is disposed normal to the said axial plane. Each guide slot 23 is adapted to snugly receive and support an elongated clamping blade 21 for radial expansive and contractive movements therein.

Clamping blades A2'( are generally T-shaped in cross-section and have two cutout portions opening at the bottom side of the blade and extending upwardly into the head portion of the blade to form two downwardly extending tongue-like portions 28 and 29, the bottom edges of which are adapted to seat upon the bottom surface 26 of the guide slot 23 when the clamping blades are in their fully contracted position. Each of the notch portions of the blade 21 has a correspondingly located end wall 3| and 32, similarly inclined with the inner edge of the blade providing cam surfaces thereon extending from the top of the notch portion to the bottom of the respective tongue-like portions 28 and 29. The cam surfaces 3| and 32 are adapted to cooperate with expanding means to impart expanding movement to the clamping blades 21 or to allow the blades to be contracted in the guide slots 23. A garter spring 33 encircles the clamping blades 21 and is received in a notch portion 34 in each blade to an extent to lie wholly inwardly of a clamping surface 35 on the blades for the purpose of urging the blades radially inwardly in contracting direction in the guide slots 23. The blades 21 are disposed in relative longitudinal alignment in the guide slots 23 between the face I2a of the fixture with which the tool is used and an inner face 36 of a thrust plate 31 disposed in abutting relation with the shoulder on the body member I0. The thrust plate 31 has radially inwardly directed lug portions 31a (Figs. Zand 5) extending inwardly of the guide slots 23 to an extent to prevent relative angular displacement of the thrust plate on the body member I0 and to terminate short of the bottom wall 26 of the guide slot to accommodate expanding means therebetween later to be described. Expansive movement of the clamping blades 21 between the faces |2a and 36 is used for the purpose of clamping the work piece, for example a connecting rod (not shown) so that all portions of the connecting rod will be in accurately aligned relation with that portion of the rod being supported by the clamping blades.

Means for imparting expansive movement to the clamping blades 21 comprises an elongated expander element 38 of general inverted U- shape in cross-section and disposed for adjustable longitudinal slide movement along the bottom surface 26 of the guide slot 23. Each expander element 38 has a longitudinal channel 39 (Figs. 2 and 5) along its under or innermost side and extending throughoutthe length of the expander element, except for the outermost end thereof, which channel has a width slightly greater than the width of the portions 28 and 29v on the clamping blades. The channel 39 pro- Vides leg portions 38a and 38h (Fig. 5) for the expander element 33, which rest upon the bottom 26 of the guide slot and equally distribute expanding pressures received on the expander element. The web portion 38e of each expander element 38 is also cut through transversely to form openings or orifices 42 and 43 therein. The Openings42 and 43 are adapted to telescopically receive the portions 28 and 29 of the clamping blades so as to allow these portions to freely extend into the channel 39 and to the bottom 26 of the guide slots 23 when the clamping blades are fully contracted. The innermost end wall of each of the openings 42 and 43 of the expander element 38 has a similarly inclined cam surface 45 and 46 shaped complementally to the cam surfaces 3l and 32, respectively, on the clamping blade 21 whereby longitudinal outward movement of the expander element will cause such cam surfaces to cooperate to radially expand the clamping blades. The arrangement of the clamping blade 2? and the expander element 33 is such that the guide slot 23 is substantially filled and the medially disposed cooperating cam surfaces equally distribute expanding pressures through the legportions 38a and 38h on each side of the bottom wall 26 to prevent angular 4 displacement and binding of the parts in the guide slot. It will be noted that the cam surfaces 3| and 32 of the clamping members 2l are considerably longer than the respective cooperating cam surfaces 45 and 46 on the expander element 38 so that the expander element is adapted to impart expanding movement to the portions 28and 29 of the clamping blades which is telescopically received in the channel portions 39 as well as those portions of the cam surfaces 3l and 32 which are disposed in the head of the clamping blades, whereby the range of expansion of the tool is increased by the extent of the portion of the cam surfaces located on the respective portions 28 and 29 of the clamping blade. It will also be noted that the length of the openings 42 and 43 is such as to permit the portions 28 and 29 of the clamping blade to move longitudinally therein when the blade is telescopically received in the channel portion 39 so that the innermost edge of the blade may substantially contact the bottom surface 26 of the guide slot when the blades are fully contracted. The expander elements 38 are longer than the clamping blades 21 and vextend through the thrust plate 31 providing end portions 38d projecting beyond the outer face of the thrust plate and to which are connected a means for longitudinally moving the expander elements in the guide slots 23. j y

Means for longitudinaly moving the expander elements axially outwardly of guide slots 23 to expand the clamping blades 21 is provided by a cage-like member 41 having radially inwardly directed tongue portions 48 (Figs. 2 and 5) adapted to be freely received in the guide slots 23 at least to an extent to prevent relative angular movement of the cage member with the body member I il. The inner end of each tongue-like portion 48 is keyed in a transverse notch portion 49 (Figs. 2, 5 and 6) adjacent the end of the expander element 38 so that axial movement of the cage member 41 results in simultaneous longitudinal movement of all the expander elements 38.

The cage member 41 is adjusted axially of the body member l0 by a knurled adjusting nut 50 which is rotatably supported on the reduced end portion I9 of the body member and is yieldably retained thereon by an annular, cup-like spring washer 5l yieldably held in engagement with the outer end of the nut 50 lby a split ring 52 disposed in a circumferential groove 53 adjacent the outer end of the body member. The inner end of the nut 56 is yieldably heldagainst an outer face 54 of the thrust plate 31 by the spring washer 5l.

An enlarged bore portion 56a is provided in the an external thread 56 on the cage member 41r whereby rotational adjustment of the nut will cause the cage and the expander element 33 to be moved longitudinally of the body member ED in accordance with the direction of rotation of the adjusting nut to expand or to allow the clamping blades 21 to contact in the guide slots 23.

In the use Yof the tool of this invention to support a connecting rod or other work piece, one bearing of the connecting rod or work piece is placed in registration with the clamping blades 21'and the adjusting nut 5l) is rotated in a direction to move the cage 41 axially outwardly of the body member IU. Because of the keyed connection provided bythe lugs 56 with the expander;

element 38, all expander elements are 'moved simultaneously outwardly with the cage 41 causright angles tothe face ofy plate I2.

the. respectivecam.- surfaces 3i and 32 on "the clamping. blades 211th radially expand the clamping-blades into contact withhthevinner wall of the connecting rodlfbearing orY workpiece. By means of the three-pointV suspension provided by the clamping blades, the nconnecting rod bearing or Work piece isxedly clamped on the mandrel at Pressures exertedon thel clampingsurf-aces 35i ofthe clamping blades are directed radially inwardly of the tool causing the cam surfaces 3|, 45 and *32; i6 tov hold the expander elements 3S against the bottom wall 26 of the guide slot 23 and further hold each of the v'expander elements axially inwardly of vthe bodymemberiiito takeup all looseness or play of the expander element with the cage lil-andthethreaded'connection of the cage with tlieadjusting-nutl 5i) -to hold the adjusting nut against the side Eli of the thrust plate 3l. 'Phecam surfaces 3l, 45e-nd 32, 46 further cooperate to hold the clamping `bladesaxially outwardly of the body `member I G -andin contact with the side 36l of the thrustplate-so `that all parts of the tool are rigidly maintained in accurate alignment.

When it is desired to remove a work-piece that has been clamped on the `expanded mandrel or when itv is desired to contract the mandrel for any reason, the `adjustingnut '59 is rotated in the opposite direction to move the cage axially invvardlyvof theguideslots 23, whereby the cam surfaces i5 andion the'expander elements are moved in contracting relation `with the respective cam surfaces 3l and 32l on the clamping blades `21 so that the garter spring E3 is effective to contract each clamping blade 2l to an extent determined by the extent of inwardly directed movement of theexpander elements. it is apparent that by arranging the tongue-like portions on each clamping blade 2l to be received telescopically in the expander elements, the clamping blades may be yexpanded and contracted a greater extent with uniformity throughout their entire range of movement and they Will retain their respective parallel alignment with the axis of the tool in all positions.

I claim:

1, An expansible mandrel comprising a body having at least one longitudinally extending slot of rectangular shape .in cross-section, a clamp member having a head portion radially slidable in said slot, anda depending portion of reduced Width adapted to be disposed adjacent the bottom of said slot in its fully contracted condition, said member having notches in and extending through said depending portion into said head portion providing depending sections corresponding edges of which are angularly shaped to provide spaced cam surfaces, an expander member mounted for slide lmovement in the bottom of said slot and having longitudinally spaced openings therein through which said depending sections pass to permit them to move to. the bottom of said slot, corresponding yends of said openings having walls shaped'complementally to said cam surfaces and engaged therewith, and means for adjusting saidv expander member longitudinally to expand saidl clamp member.

2. AnI expansible mandrel comprising a body havinga longitudinally extending slot of rectangular shape in cross-section., an expansihle member of T-shape in cross-section having its head portion slidably fitted in said slot and its stem portion projecting to the bottom of said slot in its fully contracted condition, said expansibleI member being notched through its stem-portion into said head portion providing longitudinally spaced sections, the corresponding end of each said section being angularly inclined to provide spaced cam surfaces, an expander member of inverted channel shape in cross-section having a depth greater than the depth of said stem portion mounted in the bottom of said slot and having longitudinally spaced openings through its channel-bottom portion adapted to receive said v stem sections, the walls of said openings adjacent said cam surfaces being shaped complementally thereto and seated thereagainst, said expansible member cam surfaces being longer than said expander member cam surfaces, and means for moving said expander member longitudinally.

3. An expansible mandrel comprising an elongated body having a plurality of longitudinal, circumferentially spaced slots therein, an expansible member of less'length than said slots mounted in each thereof, an expander member mounted in the bottom of each said slot and adapted for longitudinal movement thereof to .move said expansible members in expanding direction, and means for moving said expander members longitudinally comprising an adjusting member mounted on the end of said body for rotation without longitudinal movement, a second member mounted on said body member between said adjusting member and said expander members for longitudinal movement without rotation, a drive connection betweensaid adjusting and second member whereby rotation of the former moves the latter longitudinally, and means connecting said second member to said expander members.

4; An expansible mandrel comprising an elongated body having a plurality of longitudinal, circumferentially spaced slots therein, an expansible member of less length than said slots mounted in each thereof, an expander member mounted in the bottom of each said slot and adapted for longitudinal movement thereof vto move said expansible members in expanding diof said slots, a manually operable adjusting mdmi ber rotatably mounted on said body outwardly of said plate and having a cylindrical, internally threaded skirt portion adapted to seat against said plate to prevent longitudinal displacement thereof, a motion transmitting member mounted on said body portion and threadedly engaged Y with the threaded portion of saidv skirt portion,

said transmitting member having elementsY extending into said slots to prevent rotation of such member, sai-d expander member being extended through said openings past said thrust plate, and means connecting said expander member to said transmitting member within the skirt portion of said adjusting member.

5. An expansible mandrel comprising a body member having a plurality of circumferentially spaced and longitudinally disposed radial guide slots therein, expansible clamping means disposed in each said guide slotffor expansion end contraction movements therein, spring means disposed to urge said :clamping means in contractive direction in said guide slots, expanding means r disposed for axial slide movement in each said guide slot and operatively connected to said clamping means, manually operable actuating means supported on said body member and operable to impart said slide movement to said expanding means, and a thrust element disposed between said actuating means and said clamping means, whereby said spring means urges said clamping means against one side of said thrust means and urges said actuating means against the other side of said thrust Imeans to remove all operating clearances between relatively movable parts of the tool.

6. An expansible mandrel comprising a body member having a plurality of circumferentially spaced and longitudinally disposed radial guide slots therein, expansible clamping means disposed in each said guide slot for expansion and contraction movements therein, spring means disposed to urge said clamping means in contractive direction in said guide slots, expanding means disposed for axial slide movement in each said guide slot and operatively connected to said clamping means, and manually operable actuating means for said expanding means to impart said slide movement thereto, each said clamping means having a medially disposed tongue portion extending radially inwardly of said guide slot, and each said expanding means being perforate to telescopically receive said tongue portion when said actuating means is operated in a direction to allow said spring means to fully contract said clamping means, and said clamping means and expanding means having complemental cam elements cooperating to effect expansion or contraction of said clamping means when said expanding means is actuated.

7. An expansible lmandrel comprising a body having at least one longitudinally extending slot of rectangular shape in cross-section intersected by the body radius, an expansible member having a head portion snugly received for radial slide movement in said slot, and a depending portion of reduced cross-sectional area adap-ted to be disposed adjacent the bottom of said slot in its fully contracted position, said member having at least one notch in and extending through said depending portion into said head portion providing a depending section, said section having a wall angularly shaped to provide a cam surface thereon, an expander member mounted for slide movement in the bottom of said slot and having an elongated opening therein receiving said depending section to permit said section to move to the bottom of said slot, said opening having an end wall shaped complementally to said cam surface and engaged therewith, and means for adjusting said expander member longitudinally to expand said clamp member.

8. A tool of the class described comprising a body having at least one longitudinally extending slot of rectangular shape in cross section intersected by the body radius, an expansible member having a head portion radially slidable in said slot, an expander member mounted for slide movement in the bottom of said slot beneath said expansible member, one of said members having a projecting portion of reduced width with at least one notch therein having an edge angularly shaped to provide a cam surface, the other of said members having a longitudinally spaced opening through which said projecting portion passes to bring said members into telescopic relation enabling a maximum contraction movement of said expansible member, said opening having apart of its wall surface shaped complementally to the cam surface of said projecting portion to be engaged thereby and to cooperate therewith to eiect expansion of said expansible member as said expander member is moved longitudinally in one direction, and means for moving said expander member longitudinally in said one direction to effect said expansion of said expansible member.

9. A tool of the class described comprising a body having at least one longitudinally extending slot therein, an expansible member having a head portion slidably fitting in said slot for radial expansion and contraction movements, an expander member mounted in the bottom of said slot, one of said members having a reduced projecting portion having thereon at least one angular cam surface, the other of said members having a longitudinally extending elongate opening therein adapted to receive the projecting portion of the other member so as to bring said members into telescopic relation, the wall of said opening in said other member having thereon a cam surface shaped complementally to the cam surface of said projection, said cam surfaces adapted to be engaged with each other for expansion movement of said expansible member as said expanding member is moved longitudinally, and means for moving said member longitudinally to eiect said expansion of said expansible member.

10. A tool of the class described comprising a body having at least one longitudinally extending slot therein, an expansible member having a head portion slidably fitting in said slot for radial expansion and contraction movements, an expander member mounted in the bottom of said slot, one of said members having a plurality of lprojecting portions of reduced width, said projecting portions each having an angular cam surface similarly inclined, the other of said members having longitudinally extending elongate openings therein adapted to receive the projecting portions of said one of said members so as to bring said members into telescopic relation, the walls of said elongate openings having thereon cam surfaces shaped complementally to the cam surfaces of said projecting portions, said cam surfaces of said projecting portions being adapted to cooperate with the cam surfaces of the walls of said openings for expansion movement of said expansible member as said expanding member is moved longitudinally, and means for moving said member longitudinally to effect said expansion of said expansible member.

HENRY ROBERT BILLETER.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 465,075 Grantland Dec. 15, 1891 867,175 Demarchi Aug. 16, 1910 2,379,210 Alyea June 26, 1945 2,478,447 Arp Aug. 9, 1949 FOREIGN PATENTS Number Country Date 469,302 Great Britain July 22, 1937 

